I'm new to the forum, but have been collecting since I was a kid. I've had this coin in my my possession for a number of years, but honestly forgot about it until I was cleaning up. I've not been able to find other Canadian examples of this kind and wanted to get some opinions as to its value and how it could have happened.

This is a nice wrong planchet error.John Regitko has a column in the Canadian Coin News that discuss all kinds of errors and varieties.It is very interesting and informative.As far as yours is concerned,I would send it to a TPG like CCCS to get certified.It would probably sell for around $500.Would be nice to have a photo of the obverse as well.

I would get a number of opinions of what exactly it is (foreign/Canadian planchet, weights, diameters, etc). The person you mention(JR) is far from being 'the' expert in the field.... many more are more knowledgeable depending on the year/denomination I wouldn't send it in for certification until you know what it is and whether the TPG would certify it and for how much. Certification of errors/varieties is not cheap. There is a big difference on whether it was struck on a foreign planchet or an RCM planchet.